Vibrational spectroscopy and X-ray diffraction methods to establish the differences between hardwood and softwood

FT-IR spectrometry and X-ray diffraction were applied to probe the differences between pulp fibers from Eucalyptus wood (hardwood) and Norway spruce wood (softwood). Wood processing was found to induce certain structural alterations within its components depending on the type of wood and the applied procedure. These differences were established by using techniques such as; spectral comparison of wood samples with those of individual component fractions, derivative spectroscopy, bands deconvolution, etc. FT-IR spectroscopy was shown to be an important tool that provided details about the structural characteristics of hardwood and softwood samples. Using second-derivative spectra and deconvolution processes small differences between spectra became apparent that allowed correlations to be made related to wood composition. In addition a correlation was established between the integral absorptions for the various bands and lignin content as well as the lignin/carbohydrate content. Relations between various spectral characteristics and the degree of crystallinity and sample composition were established.